1. Field of the Invention
The present invention provides a method and system for exciting a driving vibration in a vibrator.
2. Related Art Statement
It has been studied to use a vibratory gyroscope as a turning angular rate sensor employed in a vehicle control system of an automobile body based on a vehicle turning rate feedback system. Such a system detects the direction of a steering wheel itself by a turning angle of the steering wheel. Simultaneously, the turning rate of the car vehicle is detected by the vibratory gyroscope. The system finds a difference by comparing the direction of the steering wheel with the actual body turning velocity, and attains a stable vehicle control by correcting a wheel torque and a steering angle on the basis of this difference.
Japanese patent publication 11-281372A mainly disclosed a vibratory gyroscope suitable for horizontal mounting using a planar vibrator. In these kinds of applications, the vibratory gyroscope is driven with a battery. It is thus necessary to reduce the consumed electric power and to lengthen the use life of the battery. It is thus desirable to inactivate the operation of the vibratory gyroscope when the vehicle stops, and to activate the gyroscope only when the vehicle starts. For this, it is indispensable to start normal operation in a short time after the vibratory gyroscope is activated and to start the detection of the position of the vehicle.